1. Field of the Invention
The present invention relates to a drawer type cooking device with an opening/closing mechanism for automatically opening and closing a drawer body.
2. Description of the Related Art
Conventionally, a large number of cooking devices such as microwave ovens with front-opening doors are proposed, but there are also proposed other types of cooking devices, such as drawer type cooking devices having drawers that open in the frontward direction. In such drawer type cooking devices, an object to be cooked is carried into a heating chamber through a door that opens by being drawn out, and after the object is cooked, it is taken out of the cooking device. Drawer type cooking devices are suitably applied to relatively large systems, so they are considered as cooking devices to be suitably adopted in kitchen units.
The present applicant has proposed in Japanese patent application laid-open publication No. 2006-038296 (patent document 1) a drawer type cooking device having a drawer body for storing objects to be cooked capable of being drawn out of the cooking device body. According to the drawer-type cooking device, a drawer body is slidably disposed with respect to a cooking device body via a slide mechanism composed of a fixed rail attached to the cooking device body having a heating chamber formed in the interior thereof and a movable rail attached to the drawer body, wherein when the drawer body occupies a stored position, the opening of the heating chamber is sealed via a door equipped to the drawer body, and the cooking device is further equipped with a means for preventing unintended operation of a microwave oscillation stop switch due to erroneous operation or pranks.
According to such drawer type cooking device, the mechanism for performing automatic opening and closing of the door integrated with the drawer body normally drives the drawer body via a reduction mechanism by a driving motor, so that when the user moves the drawer body via manual operation, the motor is driven via a force passing the reduction mechanism in the opposite direction, causing a large load to be applied on the reduction mechanism.
Therefore, the present applicant has proposed in Japanese patent application laid-open publication No. 2008-008562 (patent document 2) a drawer type cooking device having improved operability and small fear of failure of the motor and the gear unit for automatic door opening/closing operation, comprising an electromagnetic clutch for connecting and disconnecting power transmission, the path of which composed of a gear, a rack and the like, for moving a drawer body using motor output, wherein based on the selection of a user, the electromagnetic clutch can be set to connected state so that the output of the motor is used to open and close the door of the cooking device automatically, and when the door is to be opened and closed manually, the connection of the electromagnetic clutch is turned off so as to disconnect the path between the motor and prevent manual operation force from being transmitted to the motor, thereby preventing application of excessive torque load on the power transmission path and generation of back electromotive force in the motor. There are various possible configurations of an operation switch for turning the electromagnetic clutch on and off, but normally, an operation switch and a display unit for displaying the on/off of the electromagnetic clutch must additionally be provided in the operation unit, but according to such example, matters requiring the operation and decision-making of the user are increased, which leaves room for further improvement of usability.
It is possible to incorporate an open/close assistance mechanism for driving the motor in response to the operation of the user via the operation unit. Whether the door is fully-closed or fully-opened can be detected via a micro-switch or the like, and the direction of opening/closing operation in either state is restricted to one direction, so it is easy to perform an opening/closing operation in response to detecting the operation of the user. However, in midway of opening and closing the door, the possibility of the direction of manual operation of the door is not restricted to one direction, but can be in both opening and closing directions. In order to correctly detect the direction of manual operation and to set the direction of rotation of the motor correctly in response to the direction of manual operation to perform automatic opening/closing operation, the system requires a detecting means of the open/close direction and a control mechanism of the motor to the open/close assistance mechanism. Additional cost is required to provide such detecting means and control mechanism.
Therefore, one problem to be solved in the prior art is the disconnection and connection of the linkage of the drawer body and the movement mechanism in an appropriate manner corresponding to the respective opening/closing operation automatically in a simple manner when the user performs operation to open/close the drawer body either manually or automatically via electric operation.